X-Git-Url: http://plrg.eecs.uci.edu/git/?p=oota-llvm.git;a=blobdiff_plain;f=lib%2FAnalysis%2FMemoryBuiltins.cpp;h=8ddac8ffb971c7de573cd76e6e8411ef4db392d4;hp=2ec2aec4aa0e959e79906e8d8d39443ceee036f7;hb=f6f87835dae0dc05884652ef57d0c969c1ffe2a6;hpb=6629210aaf9d2e4fcbecc80b35f72108304da4b4 diff --git a/lib/Analysis/MemoryBuiltins.cpp b/lib/Analysis/MemoryBuiltins.cpp index 2ec2aec4aa0..8ddac8ffb97 100644 --- a/lib/Analysis/MemoryBuiltins.cpp +++ b/lib/Analysis/MemoryBuiltins.cpp @@ -12,10 +12,10 @@ // //===----------------------------------------------------------------------===// -#define DEBUG_TYPE "memory-builtins" #include "llvm/Analysis/MemoryBuiltins.h" #include "llvm/ADT/STLExtras.h" #include "llvm/ADT/Statistic.h" +#include "llvm/Analysis/TargetLibraryInfo.h" #include "llvm/Analysis/ValueTracking.h" #include "llvm/IR/DataLayout.h" #include "llvm/IR/GlobalVariable.h" @@ -26,18 +26,19 @@ #include "llvm/Support/Debug.h" #include "llvm/Support/MathExtras.h" #include "llvm/Support/raw_ostream.h" -#include "llvm/Target/TargetLibraryInfo.h" #include "llvm/Transforms/Utils/Local.h" using namespace llvm; +#define DEBUG_TYPE "memory-builtins" + enum AllocType { - MallocLike = 1<<0, // allocates - CallocLike = 1<<1, // allocates + bzero - ReallocLike = 1<<2, // reallocates - StrDupLike = 1<<3, - OpNewLike = MallocLike | (1<<4), // allocates; never returns null + OpNewLike = 1<<0, // allocates; never returns null + MallocLike = 1<<1 | OpNewLike, // allocates; may return null + CallocLike = 1<<2, // allocates + bzero + ReallocLike = 1<<3, // reallocates + StrDupLike = 1<<4, AllocLike = MallocLike | CallocLike | StrDupLike, - AnyAlloc = MallocLike | CallocLike | ReallocLike | StrDupLike + AnyAlloc = AllocLike | ReallocLike }; struct AllocFnsTy { @@ -61,12 +62,12 @@ static const AllocFnsTy AllocationFnData[] = { {LibFunc::ZnajRKSt9nothrow_t, MallocLike, 2, 0, -1}, // new[](unsigned int, nothrow) {LibFunc::Znam, OpNewLike, 1, 0, -1}, // new[](unsigned long) {LibFunc::ZnamRKSt9nothrow_t, MallocLike, 2, 0, -1}, // new[](unsigned long, nothrow) - {LibFunc::posix_memalign, MallocLike, 3, 2, -1}, {LibFunc::calloc, CallocLike, 2, 0, 1}, {LibFunc::realloc, ReallocLike, 2, 1, -1}, {LibFunc::reallocf, ReallocLike, 2, 1, -1}, {LibFunc::strdup, StrDupLike, 1, -1, -1}, {LibFunc::strndup, StrDupLike, 2, 1, -1} + // TODO: Handle "int posix_memalign(void **, size_t, size_t)" }; @@ -76,14 +77,14 @@ static Function *getCalledFunction(const Value *V, bool LookThroughBitCast) { CallSite CS(const_cast(V)); if (!CS.getInstruction()) - return 0; + return nullptr; if (CS.isNoBuiltin()) - return 0; + return nullptr; Function *Callee = CS.getCalledFunction(); if (!Callee || !Callee->isDeclaration()) - return 0; + return nullptr; return Callee; } @@ -94,17 +95,17 @@ static const AllocFnsTy *getAllocationData(const Value *V, AllocType AllocTy, bool LookThroughBitCast = false) { // Skip intrinsics if (isa(V)) - return 0; + return nullptr; Function *Callee = getCalledFunction(V, LookThroughBitCast); if (!Callee) - return 0; + return nullptr; // Make sure that the function is available. StringRef FnName = Callee->getName(); LibFunc::Func TLIFn; if (!TLI || !TLI->getLibFunc(FnName, TLIFn) || !TLI->has(TLIFn)) - return 0; + return nullptr; unsigned i = 0; bool found = false; @@ -115,11 +116,11 @@ static const AllocFnsTy *getAllocationData(const Value *V, AllocType AllocTy, } } if (!found) - return 0; + return nullptr; const AllocFnsTy *FnData = &AllocationFnData[i]; - if ((FnData->AllocTy & AllocTy) == 0) - return 0; + if ((FnData->AllocTy & AllocTy) != FnData->AllocTy) + return nullptr; // Check function prototype. int FstParam = FnData->FstParam; @@ -135,7 +136,7 @@ static const AllocFnsTy *getAllocationData(const Value *V, AllocType AllocTy, FTy->getParamType(SndParam)->isIntegerTy(32) || FTy->getParamType(SndParam)->isIntegerTy(64))) return FnData; - return 0; + return nullptr; } static bool hasNoAliasAttr(const Value *V, bool LookThroughBitCast) { @@ -202,50 +203,33 @@ bool llvm::isOperatorNewLikeFn(const Value *V, const TargetLibraryInfo *TLI, /// ignore InvokeInst here. const CallInst *llvm::extractMallocCall(const Value *I, const TargetLibraryInfo *TLI) { - return isMallocLikeFn(I, TLI) ? dyn_cast(I) : 0; + return isMallocLikeFn(I, TLI) ? dyn_cast(I) : nullptr; } -static Value *computeArraySize(const CallInst *CI, const DataLayout *TD, +static Value *computeArraySize(const CallInst *CI, const DataLayout &DL, const TargetLibraryInfo *TLI, bool LookThroughSExt = false) { if (!CI) - return 0; + return nullptr; // The size of the malloc's result type must be known to determine array size. Type *T = getMallocAllocatedType(CI, TLI); - if (!T || !T->isSized() || !TD) - return 0; + if (!T || !T->isSized()) + return nullptr; - unsigned ElementSize = TD->getTypeAllocSize(T); + unsigned ElementSize = DL.getTypeAllocSize(T); if (StructType *ST = dyn_cast(T)) - ElementSize = TD->getStructLayout(ST)->getSizeInBytes(); + ElementSize = DL.getStructLayout(ST)->getSizeInBytes(); // If malloc call's arg can be determined to be a multiple of ElementSize, // return the multiple. Otherwise, return NULL. Value *MallocArg = CI->getArgOperand(0); - Value *Multiple = 0; + Value *Multiple = nullptr; if (ComputeMultiple(MallocArg, ElementSize, Multiple, LookThroughSExt)) return Multiple; - return 0; -} - -/// isArrayMalloc - Returns the corresponding CallInst if the instruction -/// is a call to malloc whose array size can be determined and the array size -/// is not constant 1. Otherwise, return NULL. -const CallInst *llvm::isArrayMalloc(const Value *I, - const DataLayout *TD, - const TargetLibraryInfo *TLI) { - const CallInst *CI = extractMallocCall(I, TLI); - Value *ArraySize = computeArraySize(CI, TD, TLI); - - if (ConstantInt *ConstSize = dyn_cast_or_null(ArraySize)) - if (ConstSize->isOne()) - return CI; - - // CI is a non-array malloc or we can't figure out that it is an array malloc. - return 0; + return nullptr; } /// getMallocType - Returns the PointerType resulting from the malloc call. @@ -257,12 +241,12 @@ PointerType *llvm::getMallocType(const CallInst *CI, const TargetLibraryInfo *TLI) { assert(isMallocLikeFn(CI, TLI) && "getMallocType and not malloc call"); - PointerType *MallocType = 0; + PointerType *MallocType = nullptr; unsigned NumOfBitCastUses = 0; // Determine if CallInst has a bitcast use. - for (Value::const_use_iterator UI = CI->use_begin(), E = CI->use_end(); - UI != E; ) + for (Value::const_user_iterator UI = CI->user_begin(), E = CI->user_end(); + UI != E;) if (const BitCastInst *BCI = dyn_cast(*UI++)) { MallocType = cast(BCI->getDestTy()); NumOfBitCastUses++; @@ -277,7 +261,7 @@ PointerType *llvm::getMallocType(const CallInst *CI, return cast(CI->getType()); // Type could not be determined. - return 0; + return nullptr; } /// getMallocAllocatedType - Returns the Type allocated by malloc call. @@ -288,7 +272,7 @@ PointerType *llvm::getMallocType(const CallInst *CI, Type *llvm::getMallocAllocatedType(const CallInst *CI, const TargetLibraryInfo *TLI) { PointerType *PT = getMallocType(CI, TLI); - return PT ? PT->getElementType() : 0; + return PT ? PT->getElementType() : nullptr; } /// getMallocArraySize - Returns the array size of a malloc call. If the @@ -296,11 +280,11 @@ Type *llvm::getMallocAllocatedType(const CallInst *CI, /// then return that multiple. For non-array mallocs, the multiple is /// constant 1. Otherwise, return NULL for mallocs whose array size cannot be /// determined. -Value *llvm::getMallocArraySize(CallInst *CI, const DataLayout *TD, +Value *llvm::getMallocArraySize(CallInst *CI, const DataLayout &DL, const TargetLibraryInfo *TLI, bool LookThroughSExt) { assert(isMallocLikeFn(CI, TLI) && "getMallocArraySize and not malloc call"); - return computeArraySize(CI, TD, TLI, LookThroughSExt); + return computeArraySize(CI, DL, TLI, LookThroughSExt); } @@ -308,7 +292,7 @@ Value *llvm::getMallocArraySize(CallInst *CI, const DataLayout *TD, /// is a calloc call. const CallInst *llvm::extractCallocCall(const Value *I, const TargetLibraryInfo *TLI) { - return isCallocLikeFn(I, TLI) ? cast(I) : 0; + return isCallocLikeFn(I, TLI) ? cast(I) : nullptr; } @@ -316,37 +300,41 @@ const CallInst *llvm::extractCallocCall(const Value *I, const CallInst *llvm::isFreeCall(const Value *I, const TargetLibraryInfo *TLI) { const CallInst *CI = dyn_cast(I); if (!CI || isa(CI)) - return 0; + return nullptr; Function *Callee = CI->getCalledFunction(); - if (Callee == 0 || !Callee->isDeclaration()) - return 0; + if (Callee == nullptr) + return nullptr; StringRef FnName = Callee->getName(); LibFunc::Func TLIFn; if (!TLI || !TLI->getLibFunc(FnName, TLIFn) || !TLI->has(TLIFn)) - return 0; + return nullptr; unsigned ExpectedNumParams; if (TLIFn == LibFunc::free || TLIFn == LibFunc::ZdlPv || // operator delete(void*) TLIFn == LibFunc::ZdaPv) // operator delete[](void*) ExpectedNumParams = 1; - else if (TLIFn == LibFunc::ZdlPvRKSt9nothrow_t || // delete(void*, nothrow) + else if (TLIFn == LibFunc::ZdlPvj || // delete(void*, uint) + TLIFn == LibFunc::ZdlPvm || // delete(void*, ulong) + TLIFn == LibFunc::ZdlPvRKSt9nothrow_t || // delete(void*, nothrow) + TLIFn == LibFunc::ZdaPvj || // delete[](void*, uint) + TLIFn == LibFunc::ZdaPvm || // delete[](void*, ulong) TLIFn == LibFunc::ZdaPvRKSt9nothrow_t) // delete[](void*, nothrow) ExpectedNumParams = 2; else - return 0; + return nullptr; // Check free prototype. // FIXME: workaround for PR5130, this will be obsolete when a nobuiltin // attribute will exist. FunctionType *FTy = Callee->getFunctionType(); if (!FTy->getReturnType()->isVoidTy()) - return 0; + return nullptr; if (FTy->getNumParams() != ExpectedNumParams) - return 0; + return nullptr; if (FTy->getParamType(0) != Type::getInt8PtrTy(Callee->getContext())) - return 0; + return nullptr; return CI; } @@ -362,12 +350,9 @@ const CallInst *llvm::isFreeCall(const Value *I, const TargetLibraryInfo *TLI) { /// object size in Size if successful, and false otherwise. /// If RoundToAlign is true, then Size is rounded up to the aligment of allocas, /// byval arguments, and global variables. -bool llvm::getObjectSize(const Value *Ptr, uint64_t &Size, const DataLayout *TD, +bool llvm::getObjectSize(const Value *Ptr, uint64_t &Size, const DataLayout &DL, const TargetLibraryInfo *TLI, bool RoundToAlign) { - if (!TD) - return false; - - ObjectSizeOffsetVisitor Visitor(TD, TLI, Ptr->getContext(), RoundToAlign); + ObjectSizeOffsetVisitor Visitor(DL, TLI, Ptr->getContext(), RoundToAlign); SizeOffsetType Data = Visitor.compute(const_cast(Ptr)); if (!Visitor.bothKnown(Data)) return false; @@ -394,22 +379,24 @@ APInt ObjectSizeOffsetVisitor::align(APInt Size, uint64_t Align) { return Size; } -ObjectSizeOffsetVisitor::ObjectSizeOffsetVisitor(const DataLayout *TD, +ObjectSizeOffsetVisitor::ObjectSizeOffsetVisitor(const DataLayout &DL, const TargetLibraryInfo *TLI, LLVMContext &Context, bool RoundToAlign) -: TD(TD), TLI(TLI), RoundToAlign(RoundToAlign) { - IntegerType *IntTy = TD->getIntPtrType(Context); - IntTyBits = IntTy->getBitWidth(); - Zero = APInt::getNullValue(IntTyBits); + : DL(DL), TLI(TLI), RoundToAlign(RoundToAlign) { + // Pointer size must be rechecked for each object visited since it could have + // a different address space. } SizeOffsetType ObjectSizeOffsetVisitor::compute(Value *V) { + IntTyBits = DL.getPointerTypeSizeInBits(V->getType()); + Zero = APInt::getNullValue(IntTyBits); + V = V->stripPointerCasts(); if (Instruction *I = dyn_cast(V)) { // If we have already seen this instruction, bail out. Cycles can happen in // unreachable code after constant propagation. - if (!SeenInsts.insert(I)) + if (!SeenInsts.insert(I).second) return unknown(); if (GEPOperator *GEP = dyn_cast(V)) @@ -442,7 +429,7 @@ SizeOffsetType ObjectSizeOffsetVisitor::visitAllocaInst(AllocaInst &I) { if (!I.getAllocatedType()->isSized()) return unknown(); - APInt Size(IntTyBits, TD->getTypeAllocSize(I.getAllocatedType())); + APInt Size(IntTyBits, DL.getTypeAllocSize(I.getAllocatedType())); if (!I.isArrayAllocation()) return std::make_pair(align(Size, I.getAlignment()), Zero); @@ -456,12 +443,12 @@ SizeOffsetType ObjectSizeOffsetVisitor::visitAllocaInst(AllocaInst &I) { SizeOffsetType ObjectSizeOffsetVisitor::visitArgument(Argument &A) { // no interprocedural analysis is done at the moment - if (!A.hasByValAttr()) { + if (!A.hasByValOrInAllocaAttr()) { ++ObjectVisitorArgument; return unknown(); } PointerType *PT = cast(A.getType()); - APInt Size(IntTyBits, TD->getTypeAllocSize(PT->getElementType())); + APInt Size(IntTyBits, DL.getTypeAllocSize(PT->getElementType())); return std::make_pair(align(Size, A.getParamAlignment()), Zero); } @@ -534,7 +521,7 @@ ObjectSizeOffsetVisitor::visitExtractValueInst(ExtractValueInst&) { SizeOffsetType ObjectSizeOffsetVisitor::visitGEPOperator(GEPOperator &GEP) { SizeOffsetType PtrData = compute(GEP.getPointerOperand()); APInt Offset(IntTyBits, 0); - if (!bothKnown(PtrData) || !GEP.accumulateConstantOffset(*TD, Offset)) + if (!bothKnown(PtrData) || !GEP.accumulateConstantOffset(DL, Offset)) return unknown(); return std::make_pair(PtrData.first, PtrData.second + Offset); @@ -550,7 +537,7 @@ SizeOffsetType ObjectSizeOffsetVisitor::visitGlobalVariable(GlobalVariable &GV){ if (!GV.hasDefinitiveInitializer()) return unknown(); - APInt Size(IntTyBits, TD->getTypeAllocSize(GV.getType()->getElementType())); + APInt Size(IntTyBits, DL.getTypeAllocSize(GV.getType()->getElementType())); return std::make_pair(align(Size, GV.getAlignment()), Zero); } @@ -586,16 +573,20 @@ SizeOffsetType ObjectSizeOffsetVisitor::visitInstruction(Instruction &I) { return unknown(); } - -ObjectSizeOffsetEvaluator::ObjectSizeOffsetEvaluator(const DataLayout *TD, - const TargetLibraryInfo *TLI, - LLVMContext &Context) -: TD(TD), TLI(TLI), Context(Context), Builder(Context, TargetFolder(TD)) { - IntTy = TD->getIntPtrType(Context); - Zero = ConstantInt::get(IntTy, 0); +ObjectSizeOffsetEvaluator::ObjectSizeOffsetEvaluator( + const DataLayout &DL, const TargetLibraryInfo *TLI, LLVMContext &Context, + bool RoundToAlign) + : DL(DL), TLI(TLI), Context(Context), Builder(Context, TargetFolder(DL)), + RoundToAlign(RoundToAlign) { + // IntTy and Zero must be set for each compute() since the address space may + // be different for later objects. } SizeOffsetEvalType ObjectSizeOffsetEvaluator::compute(Value *V) { + // XXX - Are vectors of pointers possible here? + IntTy = cast(DL.getIntPtrType(V->getType())); + Zero = ConstantInt::get(IntTy, 0); + SizeOffsetEvalType Result = compute_(V); if (!bothKnown(Result)) { @@ -615,7 +606,7 @@ SizeOffsetEvalType ObjectSizeOffsetEvaluator::compute(Value *V) { } SizeOffsetEvalType ObjectSizeOffsetEvaluator::compute_(Value *V) { - ObjectSizeOffsetVisitor Visitor(TD, TLI, Context); + ObjectSizeOffsetVisitor Visitor(DL, TLI, Context, RoundToAlign); SizeOffsetType Const = Visitor.compute(V); if (Visitor.bothKnown(Const)) return std::make_pair(ConstantInt::get(Context, Const.first), @@ -634,13 +625,15 @@ SizeOffsetEvalType ObjectSizeOffsetEvaluator::compute_(Value *V) { if (Instruction *I = dyn_cast(V)) Builder.SetInsertPoint(I); - // record the pointers that were handled in this run, so that they can be - // cleaned later if something fails - SeenVals.insert(V); - // now compute the size and offset SizeOffsetEvalType Result; - if (GEPOperator *GEP = dyn_cast(V)) { + + // Record the pointers that were handled in this run, so that they can be + // cleaned later if something fails. We also use this set to break cycles that + // can occur in dead code. + if (!SeenVals.insert(V).second) { + Result = unknown(); + } else if (GEPOperator *GEP = dyn_cast(V)) { Result = visitGEPOperator(*GEP); } else if (Instruction *I = dyn_cast(V)) { Result = visit(*I); @@ -673,7 +666,7 @@ SizeOffsetEvalType ObjectSizeOffsetEvaluator::visitAllocaInst(AllocaInst &I) { assert(I.isArrayAllocation()); Value *ArraySize = I.getArraySize(); Value *Size = ConstantInt::get(ArraySize->getType(), - TD->getTypeAllocSize(I.getAllocatedType())); + DL.getTypeAllocSize(I.getAllocatedType())); Size = Builder.CreateMul(Size, ArraySize); return std::make_pair(Size, Zero); } @@ -725,7 +718,7 @@ ObjectSizeOffsetEvaluator::visitGEPOperator(GEPOperator &GEP) { if (!bothKnown(PtrData)) return unknown(); - Value *Offset = EmitGEPOffset(&Builder, *TD, &GEP, /*NoAssumptions=*/true); + Value *Offset = EmitGEPOffset(&Builder, DL, &GEP, /*NoAssumptions=*/true); Offset = Builder.CreateAdd(PtrData.second, Offset); return std::make_pair(PtrData.first, Offset); }